House of Della Gherardesca

The House of Della Gherardesca was a family of the Republic of Pisa, the sworn enemies of the House of Visconti. In 1237, Frederick II of Germany failed to reconcile the rival families, and a 1254 uprising led to the "Elders of the People" being formed as the ruling council of Pisa. In 1258, the Della Gherardesca received a third of Cagliari in Sardinia, and a marriage between the Visconti and Della Gherardesca families in the late 13th century ended their rivalry. Later, the family would rule Piombino.